ASH 2019: Landmark Response and Survival Analyses from 206 AML Patients Treated with Guadecitabine in a Phase 2 Study Demonstrate the Importance of Adequate Treatment Duration to Maximize Response and Survival Benefit. Survival Benefit Not Restricted to Patients with Objective Response

/in , ,

View Poster
Abstract # 3846 – Landmark Response and Survival Analyses from 206 AML Patients Treated with Guadecitabine in a Phase 2 Study Demonstrate the Importance of Adequate Treatment Duration to Maximize Response and Survival Benefit. Survival Benefit Not Restricted to Patients with Objective Response

Authors: Karen W.L. Yee, MD1, Gail J. Roboz, MD2, Casey L. O’Connell, MD3, Elizabeth A. Griffiths, MD4, Raoul Tibes, MD, PhD5*, Katherine J. Walsh, MD6, Wendy Stock, MD7, Guillermo Garcia-Manero, MD8, Michael R. Savona, MD9, Farhad Ravandi, MD10, Naval G. Daver, MD11, Elias Jabbour, MD8, Todd L. Rosenblat, MD, MS12*, Jean-Pierre Issa, MD13*, Xiang Yao Su, PhD14*, Mohammad Azab, MD14 and Hagop M. Kantarjian, MD8
1Leukemia Program, Department of Medical Oncology and Hematology, Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada; 2Weill Cornell/NY Presbyterian Medical Center, New York, NY; 3Keck School of Medicine, University of Southern California, Los Angeles, CA; 4Roswell Park Cancer Institute, Buffalo, NY; 5Mayo Clinic Arizona, Scottsdale, AZ; 6The Ohio State University, Columbus, OH; 7University of Chicago Medical Center, Chicago, IL; 8The University of Texas MD Anderson Cancer Center, Houston, TX; 9Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN; 10Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX; 11University of Texas MD Anderson Cancer Center, Department of Leukemia, Houston, TX; 12New York-Presbyterian/Columbia University Medical Center, New York, NY; 13Fels Institute, Temple University, Philadelphia, PA; 14Astex Pharmaceuticals, Inc., Pleasanton, CA

Background: Guadecitabine is a next generation subcutaneous (SC) hypomethylating agent (HMA) resistant to degradation by cytidine deaminase which results in prolonged in vivo exposure to the active metabolite decitabine. We conducted a phase 2 study of guadecitabine in 206 AML patients. International guidelines recommend a minimum of 4 to 6 cycles of HMA treatment to gain maximum benefit, but some suggest that treatment may not be beneficial if no response was observed after 4 cycles. No prospective studies have confirmed the correlation between an HMA number of cycles with response and survival using landmark methodology. We present here the results of landmark response and survival analyses based on number of cycles and whether patients had an objective response or not.

Methods: Landmark response (CR, CRi, or CRp based on 2003 IWG criteria, grouped together as composite CR or CRc), and overall survival (OS) analyses for patients alive at or beyond month 3 and month 5 (time of planned start of cycle 4 and cycle 6 respectively) were conducted. Landmark OS was compared between patients who received at least 4 or 6 cycles and those who did not. The landmark methodology avoids the bias of early deaths before cycles 4 and 6 attributing a survival benefit in those who did not die early and were able to get more cycles. We also compared the result in responding and non-responding patients to see if survival benefit was restricted to responding patients only.

Results: The study completed enrolment with 206 AML patients: 103 patients (50%) for each of Treatment Naïve (TN) unfit for intensive chemotherapy, and relapsed/refractory (r/r) AML. Median age was 68.5y (range 22-92y), ECOG PS ≥2 in 26%, poor risk cytogenetics in 41%, secondary AML in 26%, and median baseline BM blasts % was 40% in the total AML population. 108 patients (52.4%), and 155 patients (75%) received <4 and <6 cycles respectively. The primary reasons for treatment discontinuation before 4 and 6 cycles respectively (% from the total population of 206 patients) were early progression (20.4, and 30.6%), and early death (12.6%, and 17%). However, 9.7% and 14% discontinued treatment before 4 or 6 cycles respectively as a result other less objective reasons such as patient decision, investigator decision, or adverse events which might have been manageable without treatment discontinuation. The landmark analysis population included 161 patients for 4-cycle analysis, and 133 for the 6-cycle analysis. In those patients, there were no major differences in baseline characteristics between those who received at least 4 or 6 cycles and those who did not. In the landmark analysis comparing those who received at least 4 cycles (97 patients) and those who did not (64 patients), CRc rate was 62% vs 25% (p < 0.0001) and median OS was 13.7 m vs 6.1 respectively (HR 0.53, 95% CI 0.37-0.75, p 0.0003). In the landmark analysis comparing those who received at least 6 cycles (51 patients) and those who did not (82 patients) the CRc rate was 82.4% vs 35.4% (p < 0.0001), and median OS of 19.9 m vs 8.8 m respectively (HR 0.42, 95% CI 0.27-0.64, p <0.0001). The results were consistent when TN and r/r AML patients were analyzed separately. More interestingly the landmark OS benefit in patients who received at least 4 or 6 cycles was also evident in patients who did not have an objective CRc. Patients with no CRc who received at least 4 cycles had a median OS of 8 m vs 5.4 m in those who did not (HR 0.63, 95% CI 0.40-0.98, p 0.04). Patients with no CRc who received at least 6 cycles had a median OS of 12.9 vs 8 m in those who did not (HR 0.40, 95% CI 0.17-0.94, p 0.03).

Summary/Conclusions: In a prospective phase 2 study of 206 TN and r/r AML patients treated with the HMA guadecitabine, patients who were alive at or beyond 3 and 5 months who continued treatment for at least 4 or 6 cycles respectively achieved a highly significant response and survival benefit compared to those who discontinued treatment before cycle 4 or 6. The survival benefit was evident even in patients who did not have an objective response. Reasons for treatment discontinuation should be weighed carefully before stopping HMA treatment with guadecitabine before 4 or 6 cycles in AML patients to maximize response and survival benefit. Failure to achieve an objective response after 4 cycles should not be a reason for treatment discontinuation as long as patient can still benefit.

2019 ASH: Progression Free Survival (PFS), and Event Free Survival (EFS) from a Global Randomized Phase 3 Study of Guadecitabine (G) Vs Treatment Choice (TC) in 815 Patients with Treatment Naïve (TN) AML Unfit for Intensive Chemotherapy (IC): ASTRAL-1 Study

/in , ,

View Poster
Abstract # 4235 – Progression Free Survival (PFS), and Event Free Survival (EFS) from a Global Randomized Phase 3 Study of Guadecitabine (G) Vs Treatment Choice (TC) in 815 Patients with Treatment Naïve (TN) AML Unfit for Intensive Chemotherapy (IC): ASTRAL-1 Study

Authors: Jean-Pierre Issa, MD1*, Marco Gobbi, MD2*, Patricia L. Kropf, MD3*, Pierre Fenaux, MD, PhD4, Gail J. Roboz, MD5, Jiri Mayer, MD6, Jürgen Krauter, MD7*, Tadeusz Robak, MD8, Hagop M. Kantarjian, MD9, Jan Novak, MD, PhD10*, Wieslaw W. Jedrzejczak, MD, PhD11*, Xavier Thomas, MD, PhD12, Mario Ojeda-Uribe, MD13*, Yasushi Miyazaki, MD, PhD14, Yoo Hong Min, MD, PhD15, Su-Peng Yeh, M.D.16*, Joseph M Brandwein, MD17, Liana Gercheva, MD18*, Judit Demeter, MD19*, Elizabeth A. Griffiths, MD20, Karen W.L. Yee, MD21, Yong Hao, MD, PhD22*, Mohammad Azab, MD22 and Hartmut Döhner, MD23
1Fels Institute, Temple University, Philadelphia, PA; 2Ospedale Policlinico San Martino, Genova, Italy; 3Fox Chase Cancer Center at Temple University Hospital, Philadelphia; 4Hôpital St Louis/Université Paris 7 / Service d’hématologie séniors, Hôpital Saint-Louis, Paris, France; 5New York-Presbyterian/Weill Cornell Medical Center, New York, NY; 6Fakultní Nemocnice Brno, Brno, Czech Republic; 7Städtisches Klinikum Braunschweig gGmbH, Braunschweig, Germany; 8Medical University of Lodz, Lodz, Poland; 9The University of Texas MD Anderson Cancer Center, Houston, TX; 10Univerzita Karlova, Praha, Czech Republic; 11MTZ Clinical Research, Medical University of Warsaw, Warsaw, Poland; 12Hematology department 1 G, Centre Hospitalier Lyon Sud, Pierre Benite, France; 13GHR Mulhouse Sud-Alsace, Mulhouse, France; 14Atomic Bomb Disease Institute, Nagasaki University Hospital, Nagasaki, Japan; 15Severance Hospital, Yonsei University Health System, Seoul, Korea, Republic of (South); 16China Medical University Hospital, Taichung, Taiwan; 17University of Alberta, Edmonton, AB, Canada; 18Clinical Hematology Clinic, Multiprofile Hospital for Active Treatment “Sveta Marina”, Varna, Bulgaria; 19Semmelweis Egyetem, Budapest, Hungary; 20Roswell Park Comprehensive Cancer Center, Buffalo, NY; 21Princess Margaret Cancer Centre, Toronto, ON, Canada; 22Astex Pharmaceuticals, Inc., Pleasanton, CA; 23University Hospital of Ulm, Ulm, Germany

Background: Guadecitabine (G) is a next generation subcutaneous hypomethylating agent (HMA) resistant to degradation by cytidine deaminase which results in prolonged in vivo exposure to the active metabolite decitabine. We conducted a large global randomized phase 3 study of G vs TC of azacitidine (AZA), decitabine (DEC), or low dose Ara-C (LDAC) in 815 TN AML patients unfit for IC (ASTRAL-1 study). The ITT results for the primary endpoints of Complete Response (CR), and Overall Survival (OS) were previously presented (Fenaux et al, EHA abstract S879, 2019). There is no consensus on definition of disease progression particularly with HMA treatment which may continue to benefit patients in the absence of objective response. EFS analysis based on end of treatment benefit (treatment discontinuation, or start of an alternative therapy, or death) regardless of progression may offer a simpler way of assessing HMA treatment benefit. We describe here the results of the study based on both PFS and EFS analyses and how they compare with OS analyses in the overall ITT population, and in subgroups of patients based on number of cycles administered.

Methods: TN-AML ineligible for IC due to age ≥ 75 y, or comorbidities, or ECOG PS 2-3 were randomized 1:1 to either G (60 mg/m2/d SC for 5-days Q28 days) or a preselected TC of AZA, DEC, or LDAC at their standard regimens. AML diagnosis, and response status by IWG 2003 criteria, were assessed by an independent central pathologist blinded to randomization assignment. CR and OS were co-primary endpoints. PFS was a secondary endpoint calculated from date of randomization to the earliest date of progression by investigators or central assessment, relapse after response, start of an alternative therapy, or death. Since progression date is sometimes difficult to ascertain under HMA treatment, an EFS analysis was conducted post hoc using the concept of time to treatment failure. EFS was therefore calculated from date of randomization to the earliest date of discontinuation of randomized treatment, start of an alternative therapy, or death. PFS, EFS, and OS data are presented for the overall ITT population, and for patients who received at least 4 cycles or 6 cycles, and patients who had an objective response.

Results: 815 patients were randomized to G (408) or TC (407). Preselected TCs prior to randomization were DEC (43%), AZA (42%), and LDAC (15%). Baseline variables were well balanced across the 2 treatment arms. The majority of patients were randomized to receive an HMA: 759 patients (93%) with only 56 patients (7%) randomized to receive LDAC. In the primary ITT analysis, CR (19.4% for G and 17.4% for TC), and OS Hazard Ratio (0.97; 95% CI 0.83-1.14) were not significantly different between G and TC. An equal proportion of patients received at least 4 cycles (57.6% for G vs 59.2% for TC), or 6 cycles (45.8% for G vs 46.2% for TC) so there was no obvious bias in terms of adherence to treatment in the 2 study arms. Table shows OS, PFS, and EFS median survival, G/TC HR with 95% CI, and p values for the primary ITT population as well as for patients who received at least 4 cycles (N=476 patients), and those who received at least 6 cycles (N=375 patients). G/TC HR for all analyses favored guadecitabine (HR <1). However only OS, and EFS seemed to significantly favor G in patients who received adequate treatment duration by number of cycles. EFS was also the only analysis to significantly favor G in the overall ITT population suggesting that it may be a better predictor of OS benefit in patients who went on to receive adequate treatment with at least 4 or 6 cycles (Table). In addition, EFS also significantly favored G in patients who achieved an objective response (CR, CRp, CRi, or PR): median EFS for G 17.4 vs 14.6 m for TC, HR 0.68, 95% CI 0.5-0.93, p 0.016.

Summary/Conclusions: In a large global 815-patient randomized study of G vs TC (composed mainly of first generation HMAs), EFS analyses that do not rely on progression date which is sometimes difficult to define favored G over TC in the ITT population, and seemed to better predict OS benefit in patients who went on to receive at least 4 or 6 cycles. EFS calculated from date of randomization to the earliest date of randomized treatment discontinuation, start of alternative therapy, or death as conducted here could be a simple surrogate for cessation of treatment benefit particularly for patients treated with HMAs.

2019 ASH: Landmark Response and Survival Analyses from 102 MDS and CMML Patients Treated with Guadecitabine in a Phase 2 Study Showing That Maximum Response and Survival Is Best Achieved with Adequate Treatment Duration

/in , ,

View Poster
Abstract # 2957 – Landmark Response and Survival Analyses from 102 MDS and CMML Patients Treated with Guadecitabine in a Phase 2 Study Showing That Maximum Response and Survival Is Best Achieved with Adequate Treatment Duration

Authors: Michael R. Savona, MD1, Hagop M. Kantarjian, MD2, Gail J. Roboz, MD3, Casey L. O’Connell, MD4, Katherine J. Walsh, MD5, Raoul Tibes, MD, PhD6*, Karen W.L. Yee, MD7, Wendy Stock, MD8, Elizabeth A. Griffiths, MD9, Elias Jabbour, MD2, Scott D. Lunin, MD10*, Todd L. Rosenblat, MD, MS11*, Nikolai A. Podoltsev, MD, PhD12, Jean-Pierre Issa, MD13*, Xiang Yao Su, PhD14*, Mohammad Azab, MD14 and Guillermo Garcia-Manero, MD2

1Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Nashville, TN; 2The University of Texas MD Anderson Cancer Center, Houston, TX; 3Weill Cornell/NY Presbyterian Medical Center, New York, NY; 4USC Keck School of Medicine, University of Southern California, Los Angeles, CA; 5The Ohio State University, Columbus, OH; 6Mayo Clinic Arizona, Scottsdale, AZ; 7Princess Margaret Cancer Centre, Toronto, ON, CAN; 8University of Chicago Medical Center, Chicago, IL; 9Roswell Park Cancer Institute, Buffalo, NY; 10Sarah Cannon Research Institute, Florida Cancer Specialists, Venice, FL; 11Columbia University Irving Medical Center, New York, NY; 12Yale School of Medicine, New Haven, CT; 13Fels Institute, Temple University, Philadelphia, PA; 14Astex Pharmaceuticals, Inc., Pleasanton, CA

 

Background: Guadecitabine is a next generation subcutaneous (SC) hypomethylating agent (HMA) resistant to degradation by cytidine deaminase which results in prolonged in vivo exposure to the active metabolite decitabine. We conducted a phase 2 study of guadecitabine in 102 Myelodysplastic Syndromes (MDS), and Chronic Myelomonocytic leukemia (CMML) patients. International guidelines recommend a minimum of 4 to 6 cycles of HMA treatment to gain maximum benefit, but some suggest that treatment may not be beneficial if no response was observed after 4 cycles. No prospective studies have confirmed the correlation between an HMA number of cycles with response and survival using landmark methodology. We present here the results of landmark response and survival analyses based on number of cycles and whether patients had an objective response or not.

 

Methods: Landmark response based on 2006 IWG criteria, and overall survival (OS) analyses for patients alive at or beyond month 3 and month 5 (time of planned start of cycle 4 and cycle 6 respectively) were conducted. Objective response (OR) was defined as patients who had Complete Response (CR), Partial Response (PR), marrow (m)CR, or Hematological Improvement (HI). Landmark OS was compared between patients who received at least 4 or 6 cycles and those who did not. The landmark methodology avoids the bias of early deaths before cycles 4 and 6 attributing a survival benefit in those who did not die early and were able to get more cycles. We also compared the result in responding and non-responding patients to see if survival benefit was restricted to responding patients only.

 

Results: The study completed enrolment with 102 patients: 53 patients after HMA failure (relapsed/refractory or r/r), and 49 HMA-naive patients (Treatment Naïve or TN) with a median follow up for the entire study of 3.2 years (IQR 2.9-3.5 years). Median age was 71 and 72 years for TN MDS/CMML and r/r MDS/CMML patients respectively. Median OS was 23.4 months (m) for TN MDS/CMML patients and 11.7 m for r/r MDS/CMML patients. Of the 102 patients treated, 37 patients (36.3%) and 58 (56.9%) received less than 4 and 6 cycles respectively. The landmark analysis population was 91 patients for the 4-cycle analysis and 87 patients for the 6-cycle analysis. In those patients, the primary reasons for treatment discontinuation before cycle 4 or 6 respectively were patient decision (9.8% and 11.8%), and investigator decision (5.9% and 9.8%) while early progression accounted for 3.9% and 10.8% of those patients. There were no major baseline characteristics difference between patients who received at least 4 and 6 cycles and those who did not in the patients included in the landmark analyses. In the landmark analysis, patients who received at least 4 cycles (65 patients) had an OR rate of 68% compared to 15% in 26 patients who received <4 cycles (p <0.0001) and median OS of 20.4 m compared to 15.2 m respectively (HR 0.78, 95% CI 0.45-1.3, p 0.36). Those who received at least 6 cycles (44 patients) had an OR rate of 82% compared to 26% in 43 patients who received < 6 cycles (p<0.0001), and median OS of 23.8 m vs 13.6 m respectively (HR 0.51, 95% CI 0.3-0.85, p 0.009). Results were consistent when r/r MDS/CMML and HMA-naïve MDS/CMML were analyzed separately. Landmark OS analysis also favored those who received guadecitabine for at least 4 or 6 cycles compared to those who received <4 and < 6 cycles even in the absence of objective response (OS HR of 0.82 and 0.42 respectively) but the sample size was small to show statistical significance (p 0.58 and 0.10 respectively)

Summary/Conclusions: In a prospective phase 2 study of 102 MDS/CMML patients treated with the HMA guadecitabine, patients who were alive at the planned start of cycle 4 and cycle 6 did not continue treatment primarily because of patient or investigator decision in addition to early progression. Those who were alive and continued treatment for at least 4 or 6 cycles achieved highly significant objective response benefit compared to those who did not. Survival benefit was highly significant for those who received at least 6 cycles and was not restricted to patients who had an objective response. It is important to weigh reasons for treatment discontinuation carefully before discontinuing guadecitabine HMA treatment in MDS/CMML patients before 6 cycles to maximize response and survival benefit.

2019 ASH: Results from a Global Randomized Phase 3 Study of Guadecitabine (G) Vs Treatment Choice (TC) in 815 Patients with Treatment Naïve (TN) AML Unfit for Intensive Chemotherapy (IC) ASTRAL-1 Study: Analysis By Number of Cycles

/in , ,

View Poster

Abstract #2591 Results from a Global Randomized Phase 3 Study of Guadecitabine (G) Vs Treatment Choice (TC) in 815 Patients with Treatment Naïve (TN) AML Unfit for Intensive Chemotherapy (IC) ASTRAL-1 Study: Analysis By Number of Cycles

 

Authors: Authors: Gail J. Roboz, MD1, Hartmut Döhner, MD2, Marco Gobbi, MD3*, Patricia L. Kropf, MD4*, Jiri Mayer, MD5, Jürgen Krauter, MD6*, Tadeusz Robak, MD7, Hagop M. Kantarjian, MD8, Jan Novak, MD, PhD9*, Wieslaw Jedrzejczak, MD10*, Xavier Thomas, MD, PhD11, Mario Ojeda-Uribe, MD12*, Yasushi Miyazaki, MD, PhD13, Yoo Hong Min, MD, PhD14, Su-Peng Yeh, M.D.15*, Joseph M Brandwein, MD16, Liana Gercheva, MD17*, Judit Demeter, MD18*, Elizabeth A. Griffiths, MD19, Karen W.L. Yee, MD20, Jean-Pierre Issa, MD21*, Yong Hao, MD, PhD22*, Mohammad Azab, MD22 and Pierre Fenaux, MD, PhD23

1Weill Cornell Medicine and The New York Presbyterian Hospital, New York, NY; 2University Hospital of Ulm, Ulm, Germany; 3Ospedale Policlinico San Martino, Genova, Italy; 4Fox Chase Cancer Center at Temple University Hospital, Philadelphia; 5Fakultní Nemocnice Brno, Brno, Czech Republic; 6Städtisches Klinikum Braunschweig Städtisches Klinikum Braunschweig gGmbH, Braunschweig, Germany; 7Medical University of Lodz, Copernicus Memorial Hospital, Lodz, Poland; 8University of Texas MD Anderson Cancer Center, Department of Leukemia, Houston, TX; 9University Hospital Kralovske Vinohrady and Third Faculty of Medicine, Charles University, Prague, Czech Republic; 10Warsaw Medical University, Warsaw, Poland; 11Hematology Department, Lyon-Sud Hospital, Pierre Bénite, France; 12GHR Mulhouse Sud-Alsace, Mulhouse, France; 13Atomic Bomb Disease Institute, Nagasaki University, Nagasaki, Japan; 14Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea, Republic of (South); 15China Medical University Hospital, Taichung, Taiwan; 16University of Alberta, Edmonton, AB, Canada; 17University Hospital St. Marina, Varna, Bulgaria; 18Semmelweis University, Budapest, HUN; 19Roswell Park Comprehensive Cancer Center, Buffalo, NY; 20Princess Margaret Cancer Centre, Toronto, ON, Canada; 21Fels Institute for Cancer Research and Molecular Biology, Temple University, Philadelphia, PA; 22Astex Pharmaceuticals, Inc., Pleasanton, CA; 23Hôpital St Louis/Université Paris 7 / Service d’hématologie séniors, Hôpital Saint-Louis, Paris, France

Background: Guadecitabine (G) is a next generation subcutaneous (SC) hypomethylating agent (HMA) resistant to degradation by cytidine deaminase which results in prolonged in vivo exposure to the active metabolite decitabine. We conducted a large global randomized phase 3 study of G vs Treatment Choice (TC) with azacitidine (AZA), decitabine (DEC), or low dose Ara-C (LDAC) in 815 TN AML patients unfit for IC (ASTRAL-1 study). The primary ITT results were previously presented (Fenaux et al, EHA abstract S879, 2019). Clinical guidelines for single agent HMAs recommend a minimum of 4 to 6 treatment cycles for maximum benefit. We describe here the results of the study based on number of treatment cycles administered.

Methods: TN-AML patients ineligible for IC due to age ≥ 75 y, or coexisting morbidities, or ECOG PS 2-3 were randomized 1:1 to either G (60 mg/m2/d SC for 5-days Q28 days) or a preselected TC of AZA, DEC, or LDAC at their standard dose/schedule. AML diagnosis and response status were assessed by an independent central pathologist blinded to randomization assignment. Complete response (CR) and overall survival (OS) were co-primary endpoints. We analyzed patients’ characteristics, number of treatment cycles, reasons for treatment discontinuation, CR, and OS including analyses by number of cycles received including prospective subgroups, and OS analyses of responders and non-responders.

Results: 815 patients were randomized to G (408) or TC (407). Preselected TCs prior to randomization were DEC (43%), AZA (42%), and LDAC (15%). Baseline variables were well balanced across the 2 treatment arms. For G vs TC respectively, age ≥75 y in 62% vs 62.4%, PS 2-3 in 50.5% vs 50.4% (including 10.8% vs 8.8% PS 3), and poor risk cytogenetics in 34.3% vs 34.6%. Most patients were assigned to an HMA at randomization (759, 93%) with only 56 patients (7%) randomized to receive LDAC. Both CR (19.4% for G and 17.4% for TC), and OS Hazard Ratio (0.97; 95% CI 0.83-1.14) were similar and not significantly different between G and TC. Many patients in both arms did not receive the recommended minimum of 4 cycles (42.4% vs 40.8% for G vs TC respectively), or 6 cycles (54.2% vs 53.8% for G vs TC). The proportions were well balanced between the 2 treatment arms. Characteristics of patients who received at least 4 or 6 cycles were also well balanced between the 2 treatment arms for age, PS 2-3, secondary AML, poor risk cytogenetics, BM blasts >30%, and proliferative AML (total white cell count ≥20,000/uL). The primary reasons and proportions for treatment discontinuation were similar for the 2 treatments arms. For patients with <4 and <6 cycles respectively they are, in descending order, early deaths (16.7% and 20.7% of the overall ITT population), progression (7.6% and 11.7%), adverse events (5.8% and 6.9%), and patient decision (5.5% and 7.1%). In patients who received at least 4 cycles more patients achieved CR on G (33.6%) vs TC (28.6%), and median OS was longer on G (15.6 months for G vs 13 for TC, HR 0.78, 95% CI 0.64-0.96, log-rank p 0.02, Fig 1). Similarly, in patients who received at least 6 cycles, there were more CR on G (40.1%) vs TC (36.2%) and median OS was longer on G (19.5 months for G vs 15.0 for TC, HR 0.69, 95% CI 0.54-0.88, log-rank p 0.002, Fig 2). Subgroup analyses of OS in patients who received at least 4 or 6 cycles showed that survival benefit from G over TC was consistent in all prospective subgroups including against each of the 3 TCs (AZA, DEC, and LDAC). OS analyses in patients who received at least 4 or 6 cycles also favored G vs TC in both responders (CR, CRp, CRi, or PR) and non-responders with maximum benefit in patients who received at least 6 cycles (G vs TC OS HR 0.66, 95% CI 0.45-0.96, log-rank p 0.028 for responders, and HR of 0.73, 95% CI 0.53-1.00, log-rank p 0.048 for non-responders).

Summary/Conclusions: In a large global 815-patient randomized study of G vs TC composed mainly of first generation HMAs, G was at least as effective as TC based on the primary ITT analysis of CR and the narrow 95% CI of OS HR (0.83-1.14). Analyses of patients by number of treatment cycles showed that those who received at least 4 or 6 cycles achieved longer OS in G vs TC with the largest benefit in those who received at least 6 cycles. The benefit was observed in all subgroups, and in both responders and non-responders. Treatment with single agent guadecitabine should continue as long as the patient can still benefit and for at least 6 cycles to gain the maximum survival benefit.

 

 

2019 ASH: Durable Remission and Long-Term Survival in Relapsed/Refractory (r/r) AML Patients Treated with Guadecitabine, Median Survival Not Reached for Responders after Long Term Follow up from Phase 2 Study of 103 Patients

/in , ,

View Poster
Durable Remission and Long-Term Survival in Relapsed/Refractory (r/r) AML Patients Treated with Guadecitabine, Median Survival Not Reached for Responders after Long Term Follow up from Phase 2 Study of 103 Patients

Background: Guadecitabine is a next generation subcutaneous (SC) hypomethylating agent (HMA) resistant to degradation by cytidine deaminase which results in prolonged in vivo exposure to the active metabolite decitabine. We conducted a phase 2 study of guadecitabine in 103 r/r AML patients. We present here duration of response and long-term survival results.

Methods: We conducted a phase 2 study of guadecitabine using different regimens and doses (randomized 5-day regimen cohorts of 60 mg/m2/d vs 90 mg/m2/d SC) and a cohort of 10-day regimen in the first 1-4 cycles at 60 mg/m2/d followed by subsequent cycles of 5-day regimen). Response and duration of response were assessed using IWG 2003 criteria: Complete Response (CR), CR with incomplete platelet recovery (CRp), and CR with incomplete count recovery (CRi). CR+CRp+CRi was defined as composite CR (CRc). Overall survival (OS) was assessed using the Kaplan-Meier (KM) method. Response status for each dose/regimen cohort and the overall treated population were assessed with analyses of duration of response and long-term survival.

Results: The study completed enrolment of 103 r/r AML patients: 50 patients received 5-day regime at 60 mg/m2/d (24 patients) or 90 mg/m2/d (26 patients), and 53 patients received the 10-day (60 mg/m2/d). Median follow up was 2.4 years (29.1 months). Patients’ characteristics for the 103 r/r AML patients enrolled included median age of 60y (range 22-82y), poor risk cytogenetics in 41%, prior hematopoietic cell transplant (HCT) in 18%, median number of prior regimens 2 (range 1-10), primary refractory to induction therapy in 47%, and 41% had a high disease burden of BM blasts >40%. There was no significant difference in CR or OS between 60 and 90 mg/m2/d 5-day regimen but the CR and CRc rates were higher on the 10-day regimen (19% and 30% respectively) vs the 5-day regimen (8% and 16%). When all regimens analyzed together, 24/103 patients (23.3%) achieved CRc. Responses (CRc) were achieved in several poor prognosis subgroups including 19% in patients with poor risk cytogenetics, 31% of refractory patients, 26% of patients who relapsed after prior HCT, and 22% in patients with early relapse (< 6 months from their prior treatment). Of the 24 CRc patients, 15 (63%) were refractory to induction, 8 (33%) had poor risk cytogenetics, and 5 (21%) had prior HCT, and 14 (58%) went on to receive HCT following response. Median overall duration of response for patients with CR, and CRc were 7 and 7.8 months respectively. After long term follow up, median OS has not been reached in patients who achieved CRc (either CR or CRp/CRi). The 2-year survival rate was 57% for CR, and 50% for CRp/CRi (Fig. 1). Median OS has not yet been reached and was similar in CRc patients who went on to receive HCT post CRc (14 patients) compared to CRc patients who did not receive HCT post treatment (10 patients) (Fig.2). The 2-year survival rate was also similar for both groups (50% for those receiving HCT vs 60% for those who did not undergo HCT). Most patients were still on guadecitabine treatment until death, progression, or HCT with no other subsequent treatment. Guadecitabine was well tolerated in all cohorts with Grade 3 or higher AEs related to the drug seen in 42% of patients predominantly myelosuppression and related infections. There was no related serious AEs leading to death. The results highlight the long survival benefit for guadecitabine responders that exceeds duration of response and seems irrespective of post treatment HCT. The results also suggest that in r/r AML patients treated with guadecitabine, CRp/CRi seem to confer a similar survival benefit to CR patients suggesting that the incomplete peripheral blood count recovery may reflect continued treatment-related myelosuppression rather than active residual disease.

 Summary/Conclusions: In a phase 2 study of HMA guadecitabine in heavily pretreated r/r AML patients, 47% of whom had refractory disease, CR, CRp, and CRi all conferred long survival benefit. With a median follow up of almost 2.5 years, more than half of responding patients were still alive at 2 years and their median OS has not yet been reached. In addition, treatment with guadecitabine allowed post treatment HCT in 58% of responders.

 

2019 EHA: RESULTS OF ASTRAL-1 STUDY, A PHASE 3 RANDOMIZED TRIAL OF GUADECITABINE (G) VS TREATMENT CHOICE (TC) IN TREATMENT NAÏVE ACUTE MYELOID LEUKEMIA (TN-AML) NOT ELIGIBLE FOR INTENSIVE CHEMOTHERAPY (IC)

/in , ,

Click to view presentation:

RESULTS OF ASTRAL-1 STUDY, A PHASE 3 RANDOMIZED TRIAL OF GUADECITABINE (G) VS TREATMENT CHOICE (TC) IN TREATMENT NAÏVE ACUTE MYELOID LEUKEMIA (TN-AML) NOT ELIGIBLE FOR INTENSIVE CHEMOTHERAPY (IC)

 

Background: Guadecitabine is a next generation hypomethylating agent (HMA) given subcutaneously (SC) which provides prolonged in vivo exposure to its active metabolite decitabine, thus offering potential clinical advantages over current HMAs. A multicenter phase 2 study reported a 38% CR rate, and a 54% composite CR (CR+CRp+CRi) rate using 5-day regimen at 60 mg/m2/d SC Q28 days in TN-AML not eligible for IC (Kantarjian et al, Lancet Oncology 2017). This led to ASTRAL-1 study, an international phase 3 randomized trial comparing guadecitabine to TC of azacitidine (AZA), decitabine (DEC) or Low Dose Ara-C (LDAC).
Aims: To report ASTRAL-1 study primary analyses results.
Methods: TN-AML not eligible for IC due to age ≥ 75 y or comorbidities including ECOG PS 3 were randomized 1:1 to either guadecitabine (60 mg/m2/d SC for 5-days Q28 days) or a preselected TC of AZA, DEC, or LDAC at standard regimens. AML diagnosis and response status were assessed by an independent central pathologist blinded to randomization assignment. CR and Overall Survival (OS) were co-primary endpoints.
Results: 815 patients were randomized to guadecitabine (408) or TC (407). Preselected TCs were DEC (43%), AZA (42%), and LDAC (15%). Baseline variables were balanced across the 2 arms. Median age 76 y for both arms, patients ≥75 y were 62% vs 62.4%, PS 2-3 in 50.5% vs 50.4% (including 10.8% vs 8.8% PS 3), poor risk cytogenetics 34.3% vs 34.6%, secondary AML 36.3% vs 36.9%, WBCs ≥20×109/L 15.2% vs 14.3%, and median BM blasts 56% vs 53% for G vs TC respectively. Median follow up was 25.5 m and median number of treatment cycles was 5 for both arms. Many patients (41.6%) received ≤ 3 cycles mainly due to early death or progression with no difference between the 2 arms (42.4% on G, and 40.8% on TC). The co-primary endpoints ITT analyses showed a CR rate of 19.4% vs 17.4% for G vs TC (p = 0.48). The median, 1-y, and 2-y survival were 7.1 m, 37%, and 18% for guadecitabine, and 8.4 m, 36%, and 14% for TC (Figure 1). OS HR was 0.91, 0.98, and 0.96 for G vs AZA, DEC, and LDAC respectively. Landmark survival analyses showed potential benefit of guadecitabine vs TC in patients who received >3 cycles (median, 1-y, and 2-y OS 15.6 m, 60% and 29% on guadecitabine vs 13 m, 52%, and 20% on TC; log-rank p value=0.02, HR 0.78, 95% CI 0.64-0.96), and those who achieved any CR (CR, CRp, or CRi): OS HR 0.72, 95% CI 0.50-1.05. Analyses of predefined clinical, cytogenetics, and molecular genetics variables assessed by PCR (Flt-3 ITD, CEBPA, NPM1, and TP53) did not show significant differences of primary outcomes between guadecitabine and TC in any subgroup except for TP53. Patients with identified baseline TP53 mutations did worse on G vs TC while those without identified TP53 mutations had a more favorable outcome on guadecitabine vs TC. Both treatment arms showed overall similar safety profiles with slightly higher but not significant serious AEs incidence (81% vs 75.5%) and Grade ≥ 3 AEs (91.5% vs 87.5%) on guadecitabine vs TC respectively. There was no difference in AEs leading to death (28.7% for guadecitabine vs 29.8% for TC).
Conclusions/Summary: The trial did not achieve its primary endpoints of statistically significant superiority of guadecitabine vs TC for CR or OS. However due to the large sample size and narrow 95% CI for OS difference, the trial suggests that G is an active drug with an overall similar efficacy and safety profiles to standard therapy. Potential benefit of guadecitabine vs TC was observed in patients who were able to receive adequate treatment (>3 cycles), and those who achieved any CR. The significance of TP53 mutations needs to be further explored.
Figure 1: Kaplan-Meier Survival Plot of guadecitabine vs TC

 

2019 MDSF: Long Term Survival Results and Prognostic Factors Results of Higher Risk MDS and CMML treated with guadecitabine

/in , ,

Click here to view Publication:
Long Term Survival Results and Prognostic Factors Results of Higher Risk MDS and CMML treated with guadecitabine

 

Abstract:

Background: Guadecitabine SC (SGI-110) is a dinucleotide next generation hypomethylating agent (HMA) resistant to degradation by cytidine deaminase resulting in extended in vivo exposure to its active metabolite decitabine.

 Methods: Int, or HR MDS, and CMML patients who were either treatment-naïve (TN) or relapsed/refractory (r/r) to other HMAs were randomized to either 60 mg/m2 or 90 mg/m2 QDx5 every 28 days.

 Results: We randomized 102 patients with a median follow up of 3.2 years: 53 to 60 mg/m2 and 49 patients to 90 mg/m2 QDx5. Of those, 53 patients were TN and 49 patients were r/r MDS/CMML. Median age was 71 and 72 years for TN MDS and r/r respectively. Most baseline patient characteristics were well balanced between the 2 treatment dose groups except that more CMML patients were randomized to the 60 mg/m2 group (28%) vs. 14% in the 90 mg/m2 group, and more patients with baseline BM blasts >5% were in the 90 mg/m2 group (67%) vs. 38% in the 60 mg/m2 group. Most patients were RBC transfusion-dependent at baseline (57%). In the r/r MDS cohort, most patients (77%) received ≥6 months of prior HMA treatment.

In the TN MDS cohort the median Overall Survival (OS) was 23.4 months (25.7 months for 60 mg/m2 dose group and 18.6 months for 90 mg/m2 dose group). In the r/r MDS cohort, the median OS was 11.7 months. No statistically significant difference in response or OS was observed between the 2 dose groups. In the overall population of 102 TN and r/r MDS patients there were no major differences in OS based on DNMT3A or TET2 mutation status while patients with TP53 mutations had worse median OS (7.4 months) compared to those without TP53 mutations (22.6 months). Other baseline prognostic factors associated with worse OS were BM blasts >5%; RBC transfusion-dependence; IPSS High Risk; and ECOG Performance Status of 2 or higher.

Conclusions: The median OS of 23.4 months (25.7 months for the 60 mg/m2 dose group) in TN MDS, and 11.7 months in r/r MDS signals a promising clinical activity of guadecitabine in the treatment of higher risk MDS/CMML. A phase 3 trial (ASTRAL-3) of guadecitabine vs Physician Treatment Choice in r/r MDS and CMML patients previously treated with other HMAs is actively enrolling (ClinicalTrials.gov ID: NCT02907359).